Each observation has a date: a year, a month and a day. This chooses which of those are used to find the simulation output it is compared with. Anything a dataset does not have is simply not used, and only observations from the First to Last years are used.
- Year, month, day
- Exact dates. Each observation is compared with the simulation on the day it was made. Use this for daily, or finer, simulation output.
- Year, month
- Each observation is compared with the simulation's mean for that month of that year, and the day is ignored. Use this for monthly simulation output.
- Month, day
- Climatological: the year is ignored. Observations from any year are compared with the simulation's average for the same day of the year.
- Month
- Climatological, by month. Observations from any year are compared with the simulation's average for that calendar month.
Each point dataset below can override this with its own Match by.